【名词&注释】
辐射损伤(radiation damage)、肺动脉(pulmonary artery)、健康状况(health status)、保护层(protective layer)、风湿性心脏病(rheumatic heart disease)、剂量率(dose rate)、右心房(right atrium)、荧光屏(fluorescent screen)、肺循环高压(pulmonary circutationhypertension)、间质性肺水肿(pulmonary interstitial edema)
[单选题]诊断风湿性心脏病二尖瓣严重损害,直接的X线征象是
A. 肺循环高压(pulmonary circutationhypertension)
B. 左心房重度增大
C. 二尖瓣区钙化
D. 右心房(right atrium)重度增大
E. 重度间质性肺水肿(pulmonary interstitial edema)